I’m good at DIY projects. I’ve built most of my tanks and of all of my stands/hoods.
I once though I built the ultimate diy canister filter. I spent about $100 on it, but I retired it after about 2 months though. It worked, but it was ugly, it was difficult to maintain, and I didn’t trust that it would never leak. I chalked it up as a learning experience. I now know where to put the limit in DIY. DIY is great if you can build something that is better than what is at the LFS. If I'm just trying to save a few measly dollars by DIY, then DIY is not worth it. Filters are inexpensive, there is no major $ savings in DIY.
If you have money to burn, and can afford to make mistakes, then try a DIY Filter, but the aesthetics of DIY filters is reason alone to not DIY.